Regulating device for extraction-turbines.



W. KIESER.

REGULATING DEVICE FOR EXTRACTION TURBINES.

APPLICATION FILED DEG.23,1913.

Patented May 19, 1914.

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Wit-messes:

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UNTT STATES PATENT FFICE.

WALTER KIESER, 0F GHARLOTTENBURG, GERMANY, ASSIGNOR- TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

REGULATING DEVICE FOR EXTRACTION-TURBINES.

Specification of Letters Patent.

Application filed December 23, 1913.

Patented May 19, 1914.

Serial No. 808,374.

To all whom it may concern Be it known that I, l/VALTER Kmsnn, a citizen of the Swiss Republic, residing at Gharlottenburg, Germany, have invented certain new and useful Improvements in Regulating Devices for Extraction-Turbines, of which the following is a specification.

This invention relates to that class of steam turbines from which low pressure steam is extracted for heating, cooking, or other industrial purposes. In some of these machines, the demand for industrial steam is practically uniform, so that if the load on the turbine is not constant, requiring a variation from time to time in the amount of steam admitted to the turbine, some means must be provided for supplementing any deficiency which may be thus occasioned in the quantity of the extracted steam. To meet this condition it has been proposed to provide a valve for admitting live steam into the extraction stage, which valve is operated in connection with the nozzle valves in such a manner as to always keep the quantity of steam available for extraction purposes constant. But, again, it may happen that with such a system, one or more of the industrial steam consuming elements may be shut off after being in operation a certain length of time. This lessens the quantity of extracted steam, and, therefore, a regulating device which aims to maintain such quantity at a given constant magnitude, will not function properly.

For this reason, I have invented the regulator which forms the subject matter of the present application, the object being to maintain a uniform pressure in the extraction chamber irrespective of the variations of load upon the turbine, and of changes in the demand for extraction steam. To this end, I provide a valve which automatically opens as the nozzle valves close, and vice versa, and controls the admission of high pressure steam into the extraction chamber without passing through the wheel buckets, so that it does no work in driving the turbine, but simply supplements the steam exhausting into the extraction stage and keeps its quantity up to the predetermined magnitude. In connection with this arrangement I also make the valve responsive to the steam pressure in the extraction chamber, so that a lessened consumption for industrial purposes will not disturb the pressure in said chamber due to load conditions. In other words, the valve will maintain a proper ratio between the pressure in the extraction chamber and the quantity of steam consumcd by the industrial elements.

In the accompanying drawing, Figure 1 is a diagrannnatic section of an extraction turbine equipped with my invention, and Fig. 2 is a longitudinal section of the automatic valve on an enlarged scale.

The turbine shown is a horizontal single stage machine with two rows of buckets 1 on its single wheel 2. Steam is supplied to the buckets through nozzles 3, which for convenience of control are divided into groups, each group taking steam from its own chamber l, 5 or (5. Nozzle valves 7 control the admission of high pressure steam from the steam chest 8 to the nozzle chambers. The nozzle valves are opened in succession and closed in reverse order by a suitable actuator, such for instance as a slide 9 containing a slot 10 having cam portions 11 which operate the stems of the said valves; each stem being held locked in its open or closed position after it has been actuated by the downward or upward movement of the actuator. A load-responsive device, driven by the turbine and connected to said actuator by the lever 12 opens and closes the nozzle valves in accordance with the load on the turbine.

A separate valve 13 controls a port 14 opening from the steam chest directly into the wheel chamber 15, which is connected by the discharge pipe 16 with suitable industrial steam consuming elements. These elements normally demand a constant quantity of steam, and the valve 13 is arranged to operate inversely to the nozzle valves, opening when they close and vice versa, so that the quantity of steam entering the extraction chamber 15 will be kept constant irrespective of the changes in the load on the turbine. This is accomplished by means of a cam slot 17 in the actuator engaging the stem of said valve. Now in order to make the regulating device dependent also upon pressure changes in the extraction chamber so as to avoid disturbing the operation of the turbine when one or more consumption elements are shut off from or added to the system, the stem 18 of the valve 13 is attached to a movable abutment, preferably a piston 19 working in a cylinder 20 which has a tubular neck 21 through which the stem 18 passes. Steam from the extraction chamber is admitted under the piston 19, preferably by a passage through the stem of the valve. A spring 22 abuts against the outer face of the piston and is put under adjustable compression by a cap nut 23 screwingon the end of the cylinder 20. A stufling box 24 enables the cylinder to be screwed in and out through a nut 25 to ad just the valve 13 without escape of steam. The nut carries pins 26 which engage with the cam slot or slots 17 in the actuator.

The operation is as follows: Assume a constant load on the turbine and the valve 13 open. If now some industrial consumption elements are shut oil, then the fluid pressure in the extraction chamber 15 will rise. But this acts upon the piston 19 and causes a partial closure of the valve 13, sufficient to reduce the amount of supplemental steam entering the extraction chamber to a point where the normal pressure is restored. In case it should happen that the demand for industrial steam should be decreased to the point where it would be more than supplied by the steam admitted through the nozzle valves, a suitable relief valve (not shown) located in the extraction conduit would relieve the pressure.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means.

hat I claim as new and desire to secure by Letters Patent of the United States, is

1. The combination with an extraction turbine having nozzle valves for the admission of motive fluid thereto, of a valve admitting high pressure steam directly into the extraction chamber, and operating inversely to the nozzle valves, and means for controlling said valve by the fluid pressure in said chamber.

2. The combination with an extraction turbine, of valve means admitting steam to the buckets, an auxiliary valve means admitting high pressure steam directly into the extraction chamber, means for simultaneously controlling both said valve means,

4:. The combination with an extraction' turbine having nozzle valves for the admis sion of motive fiuld thereto, of valve means for admitting high pressure steam directly to the extraction chamber, common means for controlling said nozzle valves and valve means, said common means operating the nozzle valves and valve means in inverse order, and means controlled by the pressure in the extraction stage for operating said valve means.

5. The combination with an extraction turbine having nozzle valves for the admission of motive fluid thereto, of valve means for admitting high pressure steam directly to the extraction chamber, load-responsive means for opening and closing the nozzle valves, means operated by the opening and closing of the nozzle valves for closing and opening said valve means, and means responsive to the pressure in the extraction stage for also operating said valve means.

6. The combination with an extraction turbine having nozzle valves for the admission of motive fluid thereto, of valve means for admitting high pressure steam directly to the extraction chamber, load-responsive means for opening and closing the nozzle valves, means operated by the opening and closing of the nozzle valve for closing and opening said valve means, and means responsive to the pressure in the extraction stage for also operating said valve means, said last named means including a piston subjected on one side to the pressure in said extraction chamber and on the other side to the action of an adjustable spring.

In witness whereof, I have hereunto set my hand this 5th day of December, 1913.

IVALTER KIESER.

WVitnesses OSCAR EBERTI-I, Gusr Srnnsnoox.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. G. V 

